Honda Hawk GT NT650 1988 Service Manual page 26

TROUBLESHOOTING
ENGINE IS HARD TO START OR SOON STOPS
POSSIBLE CAUSE
1.
Drain and check fuel flow to carbure-
tor
I
REACHING CARBURETOR
2.
Try to start with choke ON
I
DOES NOT START
3.
c~eck
spark plug
I
NO PROBLEM
NOT REACHING CARBURETOR----1..... Clogged fuel line or fuel filter/
strainer
• Clogged fuel tank breather hole
Loose or disconnected fuel pump
and relay wire
Faulty fuel pump relay
Faulty fuel pump
Faulty float
Clogged carburetor body
ENGINE STARTS----------t ....,· Clogged carburetor jets
WET PLUG - - - - - - - - - - -.... - . Dirty air cleaner
Loose spark plug
Mixture too rich
Carburetor flooded
• Choke valve stuck open
Dirty air cleaner element
Cylinder flooded
Improper spark plug
WEAK OR NO S P A R K - - - - - - - .. ,· Refer to page 16-2
(ONE CYLINDER)
LOW COMPRESSION-------.....
~ ,·
Improper valve and seat contact
Damaged cylinder head gasket
Valve stuck open
Worn cylinder and piston rings
4. Spark test both cylinders
I
NO PROBLEM
5.
J,
,,1'0'"
com"","o
"'09
compression gauge
I
NO PROBLEM
6.
c~eck
valve train NO G O O D - - - - - - - - - - - -.....• Valve clearance too small
I
Improper valve timing
COMPRESSION NORMAL Worn camshaft
I .
Loose valve adjuster and lock nut
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . . . Improper ignition timing
(Faulty pulse rotor or generator with
ferrous burrs)
Clogged carburetor passage or jets
20-2